1. Field of the Invention
This invention relates to cyanoacrylate-containing compositions that include, in addition to the cyanoacrylate component, a certain accelerator to improve fixture speeds on certain substrates.
2. Brief Description of Related Technology
Cyanoacrylate adhesive compositions are well known, and widely used as quick setting, instant adhesives with a wide variety of uses. See H. V. Coover, D. W. Dreifus and J. T. O""Connor, xe2x80x9cCyanoacrylate Adhesivesxe2x80x9d in Handbook of Adhesives, 27, 463-77, I. Skeist, ed., Van Nostrand Reinhold, New York, 3rd ed. (1990). See also G. H. Millet xe2x80x9cCyanoacrylate Adhesivesxe2x80x9d in Structural Adhesives: Chemistry and Technology, S. R. Hartshorn, ed., Plenun Press, New York, p. 249-307 (1986).
Nonetheless, various techniques have been used to improve further the fixture times of such adhesive compositions for certain applications where it is important to be able to secure one substrate to another quickly, while allowing the bond strength to develop over time. In addition, substrates constructed of certain materials have proven in the past difficult to bond, irrespective of the application to which the adhesive and the substrate are to be placed.
To combat these issues, Henkel Loctite Corporation [then Loctite Corporation, at least in part through its Loctite (Ireland) Ltd. affiliate] developed a technology based on calixarene and oxacalixarene compounds. Generally, the addition of such materials to a cyanoacrylate allow for accelerated fixturing of substrates to-be-bonded together. See U.S. Pat. Nos. 4,556,700, 4,622,414, 4,636,539, 4,695,615, 4,718,966, and 4,855,461.
In addition to calixarene compounds, Henkel Loctite Corporation also developed technology based on the addition of silacrown compounds to cyanoacrylate adhesive compositions to accelerate fixturing. For instance, U.S. Pat. No. 4,906,317 (Liu) is directed to cyanoacrylate adhesive compositions which include silacrown compounds as additives to give substantially reduced fixture and cure times on de-activating substrates such as wood. The silacrown compounds are preferably employed at levels of about 0.1-5% by weight of the composition.
Henkel KGaA developed technology based on the addition to cyanoacrylate compositions of cyclodextrins to accelerate fixturing. In U.S. Pat. No. 5,312,864 (Wenz), the acceleration of the setting properties of a cyanoacrylate adhesive composition by adding thereto a hydroxyl group derivative of an xcex1-, xcex2- or xcex3-cyclodextrin which is at least partly soluble in the cyanoacrylate is described.
Other approaches have also been investigated, such as in U.S. Pat. No. 4,837,260 (Sato), in which it is reported the use of crown ethers in cyanoacrylate adhesive compositions.
More recently, Loctite (RandD) Ltd. investigated other ways in which to accelerate the curing of cyanoacrylate adhesive compositions. In U.S. Pat. No. 6,294,629 (O""Dwyer), a cyanoacrylate adhesive composition is provided with a first accelerator component selected from calixarenes and oxacalixarenes, silacrowns, cyclodextrins, crown ethers, and combinations thereof; and a second accelerator component selected from poly(ethyleneglycol) di(meth)acrylates, ethoxylated hydric compounds, and combinations thereof.
And Henkel Loctite Corporation developed a cyanoacrylate adhesive composition, based on a cyanoacrylate component; and an accelerator component consisting essentially of (i) calixarenes, oxcalixarenes, or a combination thereof, and (ii) at least one crown ether, where the composition exhibits a fixturing speed of less than 20 seconds for bonding two substrates, at least one of which is constructed of a material selected from steel, epoxy glass or balsawood, as described in U.S. Pat. No. 6,475,331 (O""Connor).
Notwithstanding the state-of-the-technology it would be desirable to provide alternative technologies to improve the fixturing speed of cyancacrylates.
The present invention is directed to a cyanoacrylate-based composition, which includes beyond the cyanoacrylate component, 
I, as an accelerator, where R is hydrogen, alkyl, alkyloxy, alkyl thioethers, haloalkyl, carboxylic acid and esters thereof, sulfinic, sulfonic and sulfurous acids and esters, phosphinic, phosphonic and phosphorous acids and esters thereof, X is optional, but when present is an aliphatic or aromatic hydrocarbyl linkage, which may be substituted by oxygen or sulfur, and Z is a single or double bond, such as 
II, where R and X are as defined above, and n is 1-12, m is 1-4, and p is 1-3.
For instance, a particularly desirable chemical class embraced by these structures is 
III, where R, Z and n are as defined above, and Rxe2x80x2 is the same as R, where g is the same as n.
A particularly desirable chemical within this class as an accelerator component is 
IV, where n and m combined is greater than or equal to 12.
The inclusion of these accelerators into a cyanoacrylate composition provides for a demonstrated improved fixture speeds, particularly on substrates constructed of certain woods, and ceramic and combinations thereof, without sacrificing shelf life.
This invention is also directed to a method of bonding together two substrates, at least one of which is constructed of certain woods, and ceramic, and combinations thereof. The method includes applying to at least one of the substrates a composition as described above, and thereafter mating together the substrates.
In addition, the present invention is directed to reaction products of the inventive compositions.
Also, the invention is directed to a method of preparing the inventive compositions.
The invention will be more fully understood by a reading of the section entitled xe2x80x9cDetailed Description of the Inventionxe2x80x9d, which follows.